This invention relates to computer enclosures. More specifically, the invention relates to techniques for locking access panels of a computer enclosure to prevent unauthorized access to components within the enclosure.
It is sometimes necessary or desirable to ensure that unauthorized persons are not able to access components contained inside the enclosure of a computer. By locking a computer enclosure shut, opportunities for theft, user injury and unauthorized reconfiguration of components may be reduced. Manufacturers have devised numerous techniques for accomplishing this purpose.
According to a first technique, a single side panel of an enclosure may be locked by fastening it to a chassis or to another panel of the enclosure. A sliding lock bar is used to prevent the panel from being disengaged. Examples of this technique may be found in several U.S. patents: In U.S. Pat. No. 6,109,710, issued to Thomas Wu et al. and assigned to Toshiba America Information Systems, Inc., a side panel of a desk top enclosure includes a sliding lock bar. The side panel is retained when protrusions on the sliding lock bar engage with protrusions on a chassis cover. In U.S. Pat. Nos. 6,157,532 and 6,053,586, issued to Stephen Cook et al. and assigned to Dell USA, L.P., a chassis of a tower enclosure includes a sliding lock bar. A side panel is retained when protrusions on the sliding lock bar prevent hooks on the side panel from being removed from the chassis. In U.S. Pat. No. 5,825,626, issued to Troy Hulick et al. and assigned to Apple Computer, Inc., a side panel of a tower enclosure includes hooks and a sliding lock bar. The side panel is retained when the hooks engage with holes in a chassis. When the sliding bar is in its locked position, the hooks are prevented from being disengaged from the chassis.
According to a second technique, two or more panels of an enclosure may be locked by fastening them to a chassis at a single point. An example of this technique may be found in U.S. Pat. No. 5,397,176, issued to Joseph Allen et al. and assigned to Compaq Computer Corporation. In that patent, two side panels of a tower enclosure each include a tab having a hole therein for receiving the bar of a padlock. A chassis also includes a tab having a hole therein. The two panels are retained when the panel tabs are aligned with the chassis tab and a padlock is passed through all three tabs.
While both of the above-described techniques serve useful purposes, each lacks one or more convenience factors. For example, each requires that an entire side of the computer enclosure must be removed to gain access to the components therein. Prior art techniques also lack flexibility: Each seems to be directed either to a tower enclosure or to a desk top enclosure, not both. It would be more flexible to have a technique that could be used either with a tower enclosure or a desk top enclosure. It would also be desirable to provide lockable access through the front or back of the enclosure as well as through the sides, top or bottom of the enclosure in a single design.
A computer enclosure according to the invention has at least first and second access panels. The access panels may be locked shut by securing them both to a chassis at a single point with a locking device. When the locking device is removed, each access panel may be opened independently of the other access panel.
In one aspect, an enclosure according to the invention includes a chassis, a first removable access panel having a first locking tab, a second removable access panel having a second locking tab, and a locking device for securing the first and second locking tabs to the chassis. The first and second locking tabs do not overlap one another. When the first and second removable access panels are mounted to the chassis, the chassis restrains the first and second removable access panels from movement in first and second orthogonal directions. When the locking device is in place, the locking device restrains the first and second removable access panels from movement in a third orthogonal direction by securing the first and second locking tabs to the chassis.
In another aspect, the front of the chassis includes a flange and a lock hole. A side of the flange facing the interior of the enclosure helps to retain the first access panel by engaging protrusions on the first access panel, thus preventing the protrusions from being pulled forward through the flange. The lock hole receives threads of a locking thumb screw. Top surfaces of the chassis define notches at each front corner of the chassis and a lip across a portion of the back of the chassis. The notches and lip on the chassis engage corresponding protrusions on the second access panel such that the second panel must be pulled forward to clear the notches and lip before it may be removed from the chassis. Each of the first and second access panels includes a locking tab that locates itself near the lock hole when the panels are mounted to the chassis. The locking tabs do not overlap one another. A head of the locking thumb screw is large enough to retain both locking tabs against the front of the chassis. As long as the locking thumb screw is fastened to the chassis, the first and second panels are prevented from being pulled forward; thus, they cannot be removed from the chassis. When the locking thumb screw is removed, however, the panels may be opened independently of one another because their locking tabs do not overlap one another.
A computer enclosure according to the invention provides convenience because it is not necessary to remove an entire side of the enclosure to access components therein. Rather, one of the access panels may constitute and entire side of the enclosure, while the other panel may constitute only a portion of one of the sides of the enclosure. For example, the first panel may be the top of the enclosure, and the second panel may be a door for accessing disk drives within the enclosure. The lockable disk drive door may be located on the front or back of the enclosure for added convenience. A single locking device may be used to secure both access panels. The invention may be applied in tower enclosures as well as in desk top enclosures.